AVS 46th International Symposium
    Applied Surface Science Division Wednesday Sessions
       Session AS-WeM

Paper AS-WeM11
The Role of SIMS for Interface Control in the MBE Growth of InGaSb/InAS Strained Layer Superlattices

Wednesday, October 27, 1999, 11:40 am, Room 6A

Session: Gaede-Langmuir Award Address and Quantitative Surface Analysis
Presenter: J.S. Solomon, Air Force Research Laboratory
Authors: J.S. Solomon, Air Force Research Laboratory
M.L. Seaford, Air Force Research Laboratory
D.H. Tomich, Air Force Research Laboratory
K.G. Eyink, Air Force Research Laboratory
Correspondent: Click to Email
Secondary ion mass spectrometry (SIMS) was used to evaluate beam flux control used for the molecular beam epitaxial (MBE) growth of an indium gallium antimonide/indium arsenide (InGaSb/InAs) strained layer superlattice. Two methods of control were compared: (1) a computer controlled mechanical shutter and (2) a computer controlled system consisting of both a mechanical shutter and a servo operated valve. The issue is the unintentional incorporation of arsenic in the InGaSb layer due to inadequacies of beam flux control mechanisms, such as shutters, to completely shield sources that are part of a cyclic growth process. Test structures of GaAs and GaSb were used in the study with the former used to evaluated antimony control and the latter used to evaluate arsenic control. SIMS results showed arsenic levels as high as 2-4% in GaSb layers when only a mechanical shutter was used. Neither arsenic nor antimony were detected in their respective test structures when growth was controlled with the combination of mechanical shutter and valve. SIMS results correlated with arsenic and antimony levels determined by high resolution x-ray diffraction (HRXRD) analysis of the same test structures. Finally, HRXRD showed improved interface integrity in the SLS structures grown using the combination of mechanical shutter and vale to control arsenic and antimony beam fluxes.